초록
<P><B>Abstract</B></P> <P>The aim of this work was to study the dilute acid pretreatment of rice straw (RS) and fermentable sugar recovery at high solid loadings at pilot scale. A series of pretreatment experiments were performed on RS resulting in >25wt% solids followed by enzymatic hydrolysis without solid-liquid separation at 20 and 25wt% using 10FPU/g of the pretreated residue. The overall sugar recovery including the sugars released in pretreatment and enzymatic hydrolysis was calculated along with a mass balance. Accordingly, the optimized conditions, i.e. 0.35wt% acid, 162°C and 10min were identified. The final glucose and xylose concentrations obtained were 83.3 and 31.9g/L respectively resulting in total concentration of 115.2g/L, with a potential to produce >50g/L of ethanol. This is the first report on pilot scale study on acid pretreatment of RS in a screw feeder horizontal reactor followed by enzymatic hydrolysis at high solid loadings.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Total solids of >25% achieved by DA pretreatment of rice straw at pilot scale. </LI> <LI> Optimum parameters were 0.35wt% acid concentration, 162°C and 10min. </LI> <LI> At a high solids (20 and 25wt%) enzymatic hydrolysis was conducted. </LI> <LI> Overall glucose recovery was 71 and 89% at 10 and 50FPU/g residue. </LI> <LI> Overall sugars (C<SUB>6</SUB> +C<SUB>5</SUB>) recovery on mass basis was 77% at 50FPU/g residue. </LI> </UL> </P>